<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\DBAL;

use PDO, Doctrine\DBAL\Types\Type, Doctrine\DBAL\Driver\Statement as DriverStatement;

/**
 * A thin wrapper around a Doctrine\DBAL\Driver\Statement that adds support
 * for logging, DBAL mapping types, etc.
 * 
 * @author Roman Borschel <roman@code-factory.org>
 * @since 2.0
 */
class Statement implements DriverStatement {
	/**
	 * @var string The SQL statement.
	 */
	private $_sql;
	/**
	 * @var array The bound parameters.
	 */
	private $_params = array();
	/**
	 * @var Doctrine\DBAL\Driver\Statement The underlying driver statement.
	 */
	private $_stmt;
	/**
	 * @var Doctrine\DBAL\Platforms\AbstractPlatform The underlying database platform.
	 */
	private $_platform;
	/**
	 * @var Doctrine\DBAL\Connection The connection this statement is bound to and executed on.
	 */
	private $_conn;
	
	/**
	 * Creates a new <tt>Statement</tt> for the given SQL and <tt>Connection</tt>.
	 *
	 * @param string $sql The SQL of the statement.
	 * @param Doctrine\DBAL\Connection The connection on which the statement should be executed.
	 */
	public function __construct($sql, Connection $conn) {
		$this->_sql = $sql;
		$this->_stmt = $conn->getWrappedConnection()->prepare( $sql );
		$this->_conn = $conn;
		$this->_platform = $conn->getDatabasePlatform();
	}
	
	/**
	 * Binds a parameter value to the statement.
	 * 
	 * The value can optionally be bound with a PDO binding type or a DBAL mapping type.
	 * If bound with a DBAL mapping type, the binding type is derived from the mapping
	 * type and the value undergoes the conversion routines of the mapping type before
	 * being bound.
	 * 
	 * @param mixed $name The name or position of the parameter.
	 * @param mixed $value The value of the parameter.
	 * @param mixed $type Either a PDO binding type or a DBAL mapping type name or instance.
	 * @return boolean TRUE on success, FALSE on failure.
	 */
	public function bindValue($name, $value, $type = null) {
		$this->_params[$name] = $value;
		if( $type !== null ) {
			if( is_string( $type ) ) {
				$type = Type::getType( $type );
			}
			if( $type instanceof Type ) {
				$value = $type->convertToDatabaseValue( $value, $this->_platform );
				$bindingType = $type->getBindingType();
			} else {
				$bindingType = $type; // PDO::PARAM_* constants
			}
			return $this->_stmt->bindValue( $name, $value, $bindingType );
		} else {
			return $this->_stmt->bindValue( $name, $value );
		}
	}
	
	/**
	 * Binds a parameter to a value by reference.
	 * 
	 * Binding a parameter by reference does not support DBAL mapping types.
	 * 
	 * @param string $name The name or position of the parameter.
	 * @param mixed $value The reference to the variable to bind
	 * @param integer $type The PDO binding type.
	 * @return boolean TRUE on success, FALSE on failure.
	 */
	public function bindParam($name, &$var, $type = PDO::PARAM_STR) {
		return $this->_stmt->bindParam( $name, $var, $type );
	}
	
	/**
	 * Executes the statement with the currently bound parameters.
	 * 
	 * @return boolean TRUE on success, FALSE on failure.
	 */
	public function execute($params = null) {
		$hasLogger = $this->_conn->getConfiguration()->getSQLLogger();
		if( $hasLogger ) {
			$this->_conn->getConfiguration()->getSQLLogger()->startQuery( $this->_sql, $this->_params );
		}
		
		$stmt = $this->_stmt->execute( $params );
		
		if( $hasLogger ) {
			$this->_conn->getConfiguration()->getSQLLogger()->stopQuery();
		}
		$this->_params = array();
		return $stmt;
	}
	
	/**
	 * Closes the cursor, freeing the database resources used by this statement. 
	 * 
	 * @return boolean TRUE on success, FALSE on failure.
	 */
	public function closeCursor() {
		return $this->_stmt->closeCursor();
	}
	
	/**
	 * Returns the number of columns in the result set.
	 * 
	 * @return integer
	 */
	public function columnCount() {
		return $this->_stmt->columnCount();
	}
	
	/**
	 * Fetches the SQLSTATE associated with the last operation on the statement.
	 * 
	 * @return string
	 */
	public function errorCode() {
		return $this->_stmt->errorCode();
	}
	
	/**
	 * Fetches extended error information associated with the last operation on the statement.
	 * 
	 * @return array
	 */
	public function errorInfo() {
		return $this->_stmt->errorInfo();
	}
	
	/**
	 * Fetches the next row from a result set.
	 * 
	 * @param integer $fetchStyle
	 * @return mixed The return value of this function on success depends on the fetch type.
	 * In all cases, FALSE is returned on failure.
	 */
	public function fetch($fetchStyle = PDO::FETCH_BOTH) {
		return $this->_stmt->fetch( $fetchStyle );
	}
	
	/**
	 * Returns an array containing all of the result set rows.
	 * 
	 * @param integer $fetchStyle
	 * @param integer $columnIndex
	 * @return array An array containing all of the remaining rows in the result set.
	 */
	public function fetchAll($fetchStyle = PDO::FETCH_BOTH, $columnIndex = 0) {
		if( $columnIndex != 0 ) {
			return $this->_stmt->fetchAll( $fetchStyle, $columnIndex );
		}
		return $this->_stmt->fetchAll( $fetchStyle );
	}
	
	/**
	 * Returns a single column from the next row of a result set.
	 * 
	 * @param integer $columnIndex
	 * @return mixed A single column from the next row of a result set or FALSE if there are no more rows. 
	 */
	public function fetchColumn($columnIndex = 0) {
		return $this->_stmt->fetchColumn( $columnIndex );
	}
	
	/**
	 * Returns the number of rows affected by the last execution of this statement.
	 * 
	 * @return integer The number of affected rows.
	 */
	public function rowCount() {
		return $this->_stmt->rowCount();
	}
	
	/**
	 * Gets the wrapped driver statement.
	 * 
	 * @return Doctrine\DBAL\Driver\Statement
	 */
	public function getWrappedStatement() {
		return $this->_stmt;
	}
}